<!DOCTYPE html>
<html>
<head>
    <title></title>
    <meta charset="utf-8">
    <style type="text/css">
        
    </style>
</head>
<body>
    <form >
 姓名：<input type="text" name="fname" placeholder="请输入姓名：" maxlength="10"/ pattern="[\d]"><br><!-- 输入0-9的数字-->
  年龄：<input type="text" name="fname" placeholder="请输入年龄：" maxlength="3"/><br>
 手机号：<input type="text" name="lname" placeholder="请输入手机号：" maxlength="11"/>
  <input type="button" value="提交"  style="height: 100px;" />
  <input type="submit" value="Submit" />
</form>

</body>
</html>